1. Field of the Invention
The present invention relates to a wireless network area limiting method and a wireless network area limiting system on the basis of near field communication (NFC).
2. Description of the Related Art
A wireless communications device has been widely used so far. This kind of wireless communications device includes, for example, a cellular phone, a tablet computer, a notebook computer, or a personal digital assistant (PDA). Users may obtain various information via the wireless communications devices, and may carry out data exchange between them. However, although the wireless communications device is very convenient for communications, at the same time, there are serious security concerns. For example, in a public place such as a coffee shop, it is very important to take into account the security of information sharing when people conduct data exchange via the wireless communications devices. That is to say, it is very necessary to limit a safe wireless network area.
For this purpose, in order to guarantee the security of wireless network connection, for example, a wireless network protocol is used to protect the security of wireless network connection by requiring a password for network access and performing MAC address filtering. However, there still is a problem of hacker attack. Generally speaking, a hacker may steal most of passwords by carrying out a large amount of calculation. For example, when an authorized user broadcasts a password for accessing a wireless network, the password may be stolen by a hacker. Furthermore, the MAC address filtering may also be cracked by using a fake user-defined MAC address generated by special purpose software.
As a result, the best way to protect a wireless network is preventing wireless network signal leakage when a wireless network signal is utilized. In other words, it is best to establish a wireless network only in a limited area such as a house, an office, a warehouse, or a building. In this case, if a hacker wants to steal a password, he must stay in the limited area where the wireless network is established. Thus, it may be said that wireless network protection extends to security protection of a physical place where a wireless network is established.
In Chinese Patent Application Publication No. 102144421A1, a method of promoting connection to a wireless local area network (WLAN) on the basis of NFC is disclosed. The aim of this method is to simplify, by utilizing the NFC, a complex interactive process when a device carries out connection to the WLAN. In particular, a NFC device is connected to a controller of a mobile communications device so as to input data received by the NFC device to the controller for processing. A user may put the mobile communications device near the NFC device located in a designated area where the WLAN is built, so that the NFC is set up. In this way, it is possible to send information related to the WLAN to a NFC reader of the mobile communications device by utilizing the NFC. Moreover, the mobile communications device does not need to search the WLAN continuously. The controller may determine whether the mobile communications device is a subscriber of the WLAN service provider, and may decide on the basis of the determined result whether or not to carry out data exchange over the WLAN. As a result, it is obvious that in this method, the NFC is just for collecting data, a safe physical area is not built, and it is necessary to predetermine wireless network information by a mobile communications device for conducting data exchange over the WLAN.
In Chinese Patent Application Publication No. 101483872A, a method of defining wireless network boundaries by utilizing a physical access control system (PACS) is disclosed. In this method, the PACS is configured to define boundaries in a wireless coverage area, and to only allow a device located in the area limited by the boundaries to access the corresponding wireless network. In particular, a control system comprises the PACS configured to control an authorized user to enter the safe area limited by the boundaries; and a wireless network generation system configured to generate a wireless network. If it is determined that an authorized user is located in the safe area, then a device related to the authorized user is allowed to access the wireless network. On the other hand, if it is determined that the authorized user has departed from the safe area, then the device related to the authorized user is not allowed to access the wireless network. However, in this method, the ID of a mobile communications device is registered in the control system in a card reading manner, and the mobile communications device is considered located in the safe area. As a result, it is obvious that the NFC is not involved in the method, and there isn't a predetermined safe physical area. That is to say, a virtual safe area is obtained by the ID registration of a mobile communications device when the mobile communications device enters a certain spatial area.
On the basis of the above, in order to guarantee the security of information exchange, the so-called “near field communication (NFC)” is adopted. The NFC is a short-distance high-frequency wireless communications technique for carrying out data exchange between devices whose distance from each other is small enough. By limiting a user involved in the communications in a certain range, it is possible to ensure the security of communications and data exchange.
In addition, at present, there, is also another indoor area limiting method in which light emitting diodes or infrared light transmitters are utilized. However, these kinds of optical signals are not stable, and are sensitive to environmental conditions. As a result, the boundaries of an area limited by utilizing this kind of method are not clear enough, and the shape of the limited area cannot be adjusted easily.